I would agree that it's probably not a good idea to compress any insulation to it's minimum volume. I use the Golite large stuff sack. Both my Delta quilt and PL Sport bag compress about as easily into it with a slight edge to the bag. The quilt is 48" wide while the bag is 60".
Drape: I think that if you compared apples to apples you would find that PL easily wins the drape contest.
Durability: The durability of both insulations has been called into question from various quarters. But I find this this post by Richard Nisley on 4/21/07 to be very interesting:
"Primaloft Sport (aka as version 2) and not Primaloft One is design optimized for loft durability in sleeping bags.
When the current generation of synthetic insulations were tested for use in the Mar's destination space suits, they noted that Primaloft Sport had the best loft durability of existing and prototype synthetics. See Mars Space Suit"
You can find the link provided by Richard in his post on 4/21/07 under the heading " Re: ?Primaloft durability question?"